Originally Posted by Blacklash
Yes. I have played hours on end in "Oblivion" with HDR+AA active and the highest possible quality settings. I only game @ 1680x though. My card is cooled with a Thermalright HR03 Plus and a 92mm Panaflo H1A fan. Idle is 45C and load after hours of "Oblivion" = 55C. That's under ambient conditions of 21C. Naturally, higher ambients will add a few C. That cooler is fantastic.
I've also tested for hours with ATiTool's stress test that has my card pumping out well over 1300FPS. If it's unstable it has yet to show in any game or circumstance.
Hardware is luck of the draw. Some cards may clock higher than others and I am certain temps are not an issue.
Hmmm 21c ambient? In the case? Thats impossible with your specs. What you live in an icebox? My ambient is 37c and its coolish in my basement lab. My core GPU temp right now is 48c. I find it QUITE suspect about that ambient. I have 2 temp monitors around my case hooked to an external display on the case. Its reporting 23c as the ambient.